Background (i.e. Post-process) data deduplication and data compression can be run on a FlexVol volume or Infinite Volume.
You can schedule a deduplication operation by creating job schedules as part of the efficiency policies or you can specify a threshold percentage, which triggers the deduplication or compression operation only after new data has exceeded the specified percentage.
You can disassociate an efficiency policy to stop running any further scheduled based deduplication and data compression operations on the volume by using the volume efficiency modify command.
A volume efficiency policy exists in the context of a Storage Virtual Machine (SVM). The volume efficiency policies support only job schedules that are of type cron."Volume efficiency" is already aliased to "sis" in cluster-shell. Apart from enabling/disabling various storage efficiency features, there are various policies that govern the behavior.
ONTAP provides following storage efficiency policies:
None: none of the storage efficiency features are enabled.
Default:dedupe is ON and deduplication operation start time is set to midnight.
--: dedupe is ON, but the user has set a different schedule than default (midnight), so policy becomes "-".
Inline: inline data compression, inline data deduplication, inline data compaction and inline data zero detection are enabled.
You can typically create policies based on:
Schedule: when the post-process operation (deduplication/compression) should start.
Data Change Rate: how much percentage of data is changed since last operation.
QoS: QoS setting
Following are the useful commands to configure deduplication policies in an ONTAP system.
Creating an Efficiency Policy
Create a volume efficiency policy named pcy1 that triggers an efficiency operation daily.